Gravitational radiation in infinite derivative gravity and connections to effective quantum gravity

Abstract

The Hulse-Taylor binary provides possibly the best test of GR to date. We find the modified quadrupole formula for Infinite Derivative Gravity (IDG). We investigate the backreaction formula for propagation of gravitational waves, found previously for Effective Quantum Gravity (EQG) for a flat background and extend this calculation to a de Sitter background for both EQG and IDG. We put tighter constraints on EQG using new LIGO data. We also find the power emitted by a binary system within the IDG framework for both circular and elliptical orbits and use the example of the Hulse-Taylor binary to show that IDG is consistent with GR.

On memory effect in modified gravity theories

“…In the large separation limits as r → ∞, erf(r) → 1 , the memory takes the usual Einsteinian form as expected. On the other hand, since IDG is a small scale modification of GR, for lower bound on mass scale of non-locality (M > 4keV ) [44], the memory reproduces the GR result above at atomic distances.…”

Weak field limit of infinite derivative gravity

“…In the large distance limits, memory is the same as the usual Einsteinian form as expected. Furthermore, for a lower bound on mass scale of non-locality (M > 4keV ) [37], the memory reduces to GR prediction above at very small distances.…”